Broaching machine



J 1937- F. J. LAPOlNTE 2,

BROACHING MACHINE Filed Oct. 2, 1955 3 Sheets-Sheet 1 Jan. 26, 1937. F. J. LAPOIINTE 2,068,834

BROACHING MACHINE Filed 001;. 2, 1955 I a Sheets-Sheet 2 Jan. 26, 1937. F. J. LAPOINTE BROACHING MACHINE s sheet-sneet 5 Filed 001;. 2, 1935 Patented Jan. 26, 1937 UNITED STATES PATENT OFFlCE- BROACHING MACHINE Francis J. Lapointe, Ann Arbor, Mich.

Application October 2, 1935, Serial No. 43,172

4 Claims.

My invention has tor its object to provide a breaching machine having a manual feed device for disposing the work in position with reference to the draw head to enable ready insertion of the broach through the work and into the draw head. The manual feed device is of particular advantage when used for placing relatively heavy pieces of the work in position with reference to the bolster plate or part of the machine that sustains the pressure of the work while it is being broached and to receive and remove the work upon the completion of the broaching operation. Preferably the feed device is located so as to dispose the work in close proximity to the part that sustains the pressure of the work during the broaching operation and from which it receives the work in order to reduce the movement of the Work when drawn againstfthe work engaging part or when released from the broach upon the completion of the broaching operation.

The invention also provides means operated automatically by the movement of the feed device for releasing the machine control elements to enable manual manipulation of the control elements and for automatically producing oper- 25 ation of parts of the machine.

The invention also consists in means for automatically maintaining the control elements in their controlling positions until they have been displaced therefrom by operations of parts of the 30 machine.

The invention may be contained in broach machines of diiferent forms, and to illustrate a practical application of the invention, I have selected a broaching machine embodying the in vention as an example of the various structures that contain the invention and shall describe the selected structure hereinafter, it being understood that certain features of my invention may be used to advantage without a corresponding use of other features of the invention and with out departing from the spirit of the invention as presented in the claims. The particular structure selected is shown in the accompanyingdrawings and described in detail hereinafter.

Fig. 2 illustrates a-dog that coacts to lock one of the control elements of the machine in its neutral position. Fig. 3 illustrates a top view of an automatic switch that is operated by one of the mov-.

Fig. 1 illustrates a side view of the machine.

of a section taken on the plane of the line 55- indicated in Fig. 4. Fig. 6 is a detail of the automatic control switch, parts of which are shown in Fig. 3. Fig. 7 illustrates an adjustable stop for the feeding device to limit its work feeding movement. Fig. 8 is a view of a section of a broach operating part of the machine. Fig. 9 illustrates a section showing the valves that control the broach actuating parts of the machine. Fig. 10 illustrates a view of a section of parts of the control elements of the machine. Fig. 11 illustrates diagrammatically the electric connection between electrically controlling and electromagnetically controlled parts of the machine.

The broaching machine illustrated in the drawings is provided with a suitable base part I and 15 frame 2 that may be enclosed together with the working parts of the machine by sheet metal side parts and hingedly connected parts. The machine is also provided with suitable ways 4 for guiding the hydraulically or operated pressure on means that reciprocates the broach. Preferably the machine is provided with a movable cylinder 6 integrally formed with a relatively broad plate 5 Whose edges are located in the ways 4 that operate to guide the cylinder in its reciprocatory movements as produced by a. fixed piston I. A suitable tube or pipe 8 of relatively large diameter is rigidly connected to the piston 1 and to the base I. The piston l is provided with suitable passageways 9 that communicate with the interior of the cylinder 6 on the lower side of the piston 1 and with the interior of the pipe 8 to admit oil under pressure from the pipe 8 into the cylinder 6 and for exhausting or returning oil to the reservoir. The cylinder 6 is also provided with a suitable head l2 through which extends a pipe l3 that communicates with the cylinder 6 above the piston l. The pipe I3 is sealed in the head I! by suitable packing means of the form well known in the art. The end of the pipe l3 terminates preferably in a position in close proximity to the upper side of the piston H! to produce a maximum cylinder stroke. Suitable pipes i 5 and I6 are connected to the pipes 8 and I3 and to the valve casing ll through which oil under pressure maybe directed to the cylinder 6 on one side of the piston, and oil may be exhausted from the cylinder on the opposite side of the piston according to the direction in which movement of the cylinder f is to be induced by the hydraulic pressures transmitted through the oil. I

The oil movement through the pipes l5 and I6 is controlled by a movable valve element I9 1ocated in the casing which is controlled in its position by suitable manual control elements that 55 control the operations of the machine. The valve casing I1 is connected to a pump 20 by means of a pipe 2|. The pump 20 may be driven by a suitable source oi power. The pipe 2i is connected to a passageway 22 that communicates with the chamber in which the valve element I9 is located. The valve element I9 is of the piston type, it being provided with a pair of channeled heads 23 and a pair of piston heads 24 that are slidably supported within the valve chamber of the valve casing ii. The piston heads 24, when operated alternately, open the passageways of the valve casing to which the pipes I5 and I6 are connected and are enabled, through the channels of the channeled heads 23, to exhaust the cylinder from the end other than the one receiving the pressure through the pipe 2|. The valve casing is provided with a passageway 25 that communicates with the valve chamber at its ends. The pipe 26 is connected to the passageway 25 and communicates with the interior of the reservoir 21 in which the pump 20 is located and from which it receives the oil that is subjected to pressure and transmitted through one or the other of the pipes I5 or I6 to reciprocate the movable cylinder 5.

The valve element I9 is operated by the manual control means of the machine. The machine is provided with a. lever 30 that is supported on a shalt 3i located in suitable bearings formed in the frame 2 of the machine and is provided with an arm 32 that is connected to the valve rod 33, and when the lever 30 is operated, the movable valve element I9 is slidably moved in the valve casing ii to shift the movablevalve element to direct the pressure and return flow of the oil to reciprocate the cylinder.

The cylinderi and its heavy guide plate 5 is provided with an over-hanging draw plate or bracket 36 braced by the wings and towhich is connected a draw head 31 having means for automatically connecting the draw head with a broach, such as the broach 38, upon movement of the cylinder in advance of its working stroke and for automatically disconnecting the broach from the draw head upon the completion of the return of the cylinder. The draw head 31 is of the type wherein pressure of a part of the draw head against a fixed part of the machine releases the broach, and upon movement of the draw head from said fixed part and a following movement of the broach, it connects the broach with the draw head. Also, upon engagement oi the fixed part upon the return of the draw head. the broach is released.

In the usual operation of the broaching machine, the work is disposed intermediate the broach and a work supporting part of the machine, and the broach is inserted through the work and into the draw head and is maintained in that position until the draw head is moved away from the work supporting part of the machine, whereupon the draw head operates to lock the broach to the draw head and draw the broach through the work. 1

The breaching machine. is provided with a work engaging table or bracket 39 that is secured- .to the frame of the machine and may be provided with a suitable fixture 40 for holding the work in a. desired fixed position to locate the opening that is to be finished or cut by the broach in alignment with the movement of the draw head. Thus the draw head may engage -the bracket 39, or the fixture 43, or any other suitable fixed part that will permit movement or the brooch head into the draw head. Also the machine is provided with means for withdrawing the broach from the draw head in order to enable placement of the work in position with reference to the draw head, and to subsequently raise the broach to insert it through the work and into the draw head, and to follow the draw head in its initial movement until the draw head engages the end of the broach.

In the form of construction shown, the broaching machine is provided with a pressure means for receiving the broach from the draw head and returning it to the draw head comprising a piston and cylinder supported on the shelf 42 of the machine. Preferably the piston is fixed, and the cylinder is slidably movable relative to the piston, oil under pressure being directed through the piston rod to parts of the cylinder located on one or the other of the sides of the piston. The cylinder 43 is slidably supported on a pair of rods 44 that depend from the shelf 42 by means of a pair of wings having sleeves 45. The extent of movement of the cylinder may be limited by suitable rings 46 that are secured to the ends of the rods 44 by means of the nuts 41. A piston 48 is supported by a pair of depending tubes 49 and 50 coaxially disposed, one within the other, and

communicating with a head 5| supported on the shelf 42 and having passageways that communicate with the interior of the pipes 49 and 50. The pipes communicate with the cylinder on opposite sides of the piston.

The head 5i is connected by means of the pipes 52 and 53 with the valve casing I! that also has passageways controlled by a piston valve 54 similar in form to the piston valve I9 except that it is smaller. It is provided with the channeled heads 55 and the piston heads 56 that slidably move in the valve chamber 51. The valve casing I1 is also provided with a passageway 58 that extends to opposite ends of the valve casing and is connected to'the return pipe 59 that communicates with the interior of the reservoir 21. The heads 55 are channeled to permit exhaustion of the oil from the parts of the cylinder 43 located on one or the other of the sides of the piston 48. Oil under pressure is directed from the pump 60 through the pipe 6i shown broken in Fig. 4, to the passageway 62 in the casing I1, whereby oil may be directed through either the pipe 52 or the pipe 53 to the cylinder 43 on one side of the piston 48 and exhausted through the other side of the piston according to the position of the movable valve member 54.

The movable valve member 54 is controlled electro-magnetically by switches that are opened and closed by the feeding means. The work is fed into position to locate the work in alignment with the broach and the draw head by means of a work carrying slide 64 located in guide ways 65 that may be connected to the work supporting bracket 39. The work carrying slide is located so as to slidably support the work and move it into a position such that the opening that is to be finished or cut is disposed in alignment with the broach and the draw head. It is particularly adapted for use where the pieces of the work are relatively heavy. It affords a means for accurately locating the work in advance of the initial operation of the machine and the engagement of the broach. The work carrying slide 54 may be provided with a fixture 63 that may be shaped to conform to the exterior of the work, and to position the slide accurately with reference to the opening-and the draw head. The guide ways may be provided with a suitable adand the broach.

Inasmuch as the broach is raised to cause its head and theshank to pass through the work when the work has been accurately positioned, a means is preferably provided whereby the work carrying slide electrically controls the operation of the cylinder 43 to raise the broach 38 and passits shank through the work and the head of the broach into the.draw head 31 and also to press the locking head 61 against the head 31 and follow the head 31 a short distance and until the broach head 61 is locked in the draw head 31. A spring pressed switch 18 is located in position in one of the ways 65 to .close the circuit by the work carrying slide 65 substantially at the time that the slide reaches the limit of its inward movement to dispose the work in position. The switch I8 is located in the circuit of the main lines II and I2, and when closed the current flows through a solenoid I3 'anda solenoid 14. The

core of the solenoid I4 is connected to the valve rod 15 and operates to raise the movable valve member 54 against the tension of the spring 16. 'fihe spring 16 is connected to the valve rod I5 'and to the valve casing I1 and operates to return the movable valve member-to its initial position when the solenoid 14 is de-energized. When, therefore, the work carrying slide 64 is pushed inward against the stop 66, the movable valve member 54 is el'ectro-magnetically actuated to 40 I! for receiving a part 88 projecting centrally from the lower end of the broach 38. The broach 33 is supported and held in alignment with the draw head 31 by the seat 19. The cylinder 43 moves the locking head 61 of the broach through the work and into the draw head and presses the upper end of the locking head '61 against the draw head 31 when the switch 18' is closed by the slide.

when the broach has been located in position to be locked into the drawhead, the cylinder 6 is raised to cause the broach to perform its working stroke. The lever 38 is lowered to raise the movable valve member I9 and direct the flow oi the fluid through the pipe I8 to a'point above the piston I. The lever 38 may be connected to a sleeve slidably supported in a bracket 83 secured to the side of the machine. The lever 38 is connected to the sleeve 82 by means of the pin 84. A dog 85 is located in a socket part formed on the bracket 83. The dog 85 is spring pressed by means of the spring 81 located inof the recesses 89 and the lever is held in position. when the lever 38 is raised, the dog 85 engages in the intermediate recess 89 which is the neutral position of the lever. When the lever is further raised, the dog 85 engages in the lower a oi. the recesses 89; Thus, the dog 85 operates to hold the lever 38 in the position to which it is moved.

The sleeve '82, when located in its normal position, is held locked by means of a pair of locking members or earns 92 located at the ends of the sleeve 82 and disposed so as to normally engage opposite ends of the sleeve 82 and prevent movement of the sleeve 82, and consequently prevent movement of the lever 38 until the locking cams are moved from their position of engagement with the ends of the sleeve 82.

The cams 92 are pivotally mounted on brackets 93, and rods 94 are connected to the locking earns 92 and to cores 95 of the solenoids l3 and 96.

When, therefore, the work carrying slide 64 is pushed inwardly toclose the switch I8, it establishes'a circuit, not only through the solenoid I4 to operate the movable valve member 54, but

also the solenoid I3 which removes the locking cam 92 from the lower end of the sleeve 82 and permits the downward movement'of the lever 30 to raise the movable valve member I9 and direct oil under pressure into the upper end of the cylinder 6.

The cylinder 6 then moves the'draw head upward, and the continued pressure of the oil in the upper end of the cylinder 43 pushes the broach 38 upward against the draw headand moves the broach upward with the upward movement of the cylinder 6 until after the draw head locks the head of the broach to the draw head. Continued upward movement of the cylinder 6 draws the broach through the work until thebroach completes its cutting stroke, whereupon the lever 38 is returned to its normal position to restore the movable valve member I9 to normal position.

The lever 38 isrestored to its normal position by means of the rod 98 that is connected to a bracket 99 that may be secured to the wings or braces 35 of the drawhead bracket 36. The rod 98'is provided with a pair of adjustable stops I88 and I8I. The stop I88 engages the sleeve 82. The broach is carried upward until the working stroke of the broach is completed and the stop I88 engages and moves the sleeve 82 until-it engages the locking cam 92 and is eng'aged by the dog 85 in the central recess 89 that locks the lever in its neutral position. Meantime the solenoid 14 is maintained energized which maintains the movableyalve member 54 in position to maintain pressure in the upper end of the cylinder 43 to hold the bracket I8 in its uppermost position.

The broach having been drawn through the work, the work carrying slide 64 is withdrawn which opens the switch I8. To prevent the reverse movement of the cylinder 43 an auxiliary circuit through the solenoid I4 is closed by means of a spring pressed switch' I 83. The

' switch I83 is suitably supported in the shell I84 and has an arm I85 that carries a roller I86, and the bracket 99 is provided with a cam I81 that may be positioned to operate the roller I86 when the drawhead returns. The switch I83 is normally maintained open and is closed when the rod 98 is drawnfrom'its normal position, namely when the drawhead is liftedfrom the work engaging bracket 39. The circuit to the solenoid V I4 is not only through the switch I8, but also through the switch I83, and upon withdrawal of the work carrying slide 64 to open the switch 18, the switch I83 maintains the solenoid I4 energized, and the cylinder 43 is held in its uppermost position.

When the slide is withdrawn from beneath the work engaging bracket 39, the switch I88 is operated. The switch I88 is a spring pressed switch similar in form to the switch 70, and is located in one of the guideways of the slide and so disposed therein as to be operated upon thevwithdrawal of the slide. The switch I08 completes the circuit from the main line 12 to the solenoid 98 that operates to actuate the upper of the cams 92 and withdraw the cam from the end of the sleeve 82 whereupon the lever 30 may be operated to lower the valve member l9 and cause the return movement of the cylinder 6. Return movement is prevented by the upper of the cams 92 which holds the sleeve 82 locked against manual movement to cause the return of the cylinder until the work is removed from beneath the broach, that is, until the switch N18 is closed. This prevents damage to the work and the broach. It also prevents forcing the work against the slide 64. The work having been removed, the broach moves down to its seat 79 located on the bracket 18, the seat being held in its delivery position bythe continued energization of the coil 14 .which is maintained closed, 1

notwithstanding the opening of the switch 79. The di'awhead pushes the lower cylinder 43 the distance that the cylinder 43 followed the draw-- head upward upon the initial rise of the drawhead. As the drawhead 31 engages the fixture 40 or the bracket 39 or other fixed part of the machine from whence it started upward and releases the brcach, the switch I03 is opened by the cam 101, and the solenoid is deenergized, and the spring 15 moves the movable valve member 54 downward and in position where'the pressure is directed through the pipes 53 to the lower end of the cylinder 43 to move the cylinder 43 and the broach supporting bracket 18 downward and withdraw the broach beneath the work carrying slide 64. Also, as the cylinder 6 approaches its neutral position, the sleeve 82 is engaged by the stop IOI located on the rod 98 which moves the lever 30 to its neutral position, and again the sleeve is engaged by the dog 85 in the central recess 89 to maintain the lever 30 in its neutral position. A succeeding piece of work is again placed upon the slide, and the slide moved inward to open the switch I08 which deenergizes the solenoid 96 and permits the cam 92 to engage the end of the sleeve 82. Also, the switch i0 is closed and the succeeding operations of the machine are performed as described.

I claim:

1. In a broaching machine, a drawhead, means for reciprocating the drawhead, a lever for controlling said means, a locking means for preventing the movement of the lever, a work engaging member, a work supporting member operable to move the work in broach engaging position, means operated by the work supporting member for controlling the lever locking means for preventing movement of the lever until the work supporting member has moved the work into broach engaging position.

2. In a broaching machine, a draw head, a hydraulic pressure means for reciprocating the draw head, a source of supply of liquid under pressure, a valve directing liquid under pressure to the hydraulic pressure means, a lever for operating the said valve, a rod operated by the pressure means, a sleeve located on the rod and connected to the lever, adjustable stops located on the rod and on opposite sides 01 the sleeve for engaging the ends of the sleeve for moving the lever, means for yieldingly resisting the movement of the sleeve.

3. In a broaching machine, a draw head, means for operating the draw head, a broach and a broach moving means for moving the broach to the draw head, a work engaging member located intermediate the draw head and the said broach moving means for holding the work upon operation of the draw head, a movable work supporting member movable between the said work engaging member and the said broach moving means for locating the work above the broach and in position to be engaged by the work engaging member when the broach is operated by the draw head, and means operated by the movable work supporting member for initiating the movement .of the broach moving means, and means controlled by the movement of the said broach moving means for initiating the operation of the draw head by the first named means.

4. In a breaching machine, a work engaging member, a work supporting member slideably supported with respect to the work engaging member, a draw head located on one side of the work engaging member, a broach moving means for supporting the broach on the other side of the work engaging member, means operated by the slide member for initiating the sequential operation of the breach moving means and the draw head, the said broach'operable to engage and release the work from the work supporting member and press the work against the work engaging member as the broach is moved.

FRANCIS J. LAPOINTE. 

